Re: [PATCH v2 1/6] ARM: dra762: hwmod: Add MCAN support

[Tero Kristo <t-kristo@ti.com>]

On 30/05/18 18:54, Tony Lindgren wrote:
> * Tero Kristo <t-kristo@ti.com> [180530 15:44]:
>> On 30/05/18 18:28, Tony Lindgren wrote:
>>> * Tero Kristo <t-kristo@ti.com> [180530 15:18]:
>>>> For the OCP if part, I think that is still needed until we switch over to
>>>> full sysc driver. clkctrl_offs you probably also need because that is used
>>>> for mapping the omap_hwmod against a specific clkctrl clock. Those can be
>>>> only removed once we are done with hwmod (or figure out some other way to
>>>> assign the clkctrl clock to a hwmod.)
>>>
>>> Hmm might be worth testing. I thought your commit 70f05be32133
>>> ("ARM: OMAP2+: hwmod: populate clkctrl clocks for hwmods if available")
>>> already parses the clkctrl from dts?
>>
>> It maps the clkctrl clock to be used by hwmod, if those are available. We
>> didn't add any specific clock entries to DT for mapping the actual clkctrl
>> clock without the hwmod_data hints yet though, as that was deemed temporary
>> solution only due to transition to interconnect driver. I.e., you would need
>> something like this in DT for every device node:
>>
>> &uart3 {
>>    clocks = <l4per_clkctrl UART3_CLK 0>;
>>    clock-names = "clkctrl";
>> };
>>
>> ... which is currently not present.
> 
> Hmm is that not the "fck" clkctrl clock we have already in
> the dts files for the interconnect target modules?

Oh okay, yeah, we could parse that one, but currently it is not done, 
and is not present for everything either I believe.

> We can also use pdata callbacks to pass the clock node if
> needed. But I guess I don't quite still understand what we
> are missing :)

So, what is missing is the glue logic only from the hwmod codebase. 
Right now this is not supported but should be relatively trivial thing 
to add if we really want to do this.

-Tero
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